A022020 Define the sequence S(a(0),a(1)) by a(n+2) is the least integer such that a(n+2)/a(n+1) > a(n+1)/a(n) for n >= 0. This is S(3,9).

3, 9, 28, 88, 277, 872, 2746, 8648, 27236, 85778, 270153, 850832, 2679649, 8439409, 26579461, 83710572, 263641910, 830325909, 2615066456, 8236010096, 25938867499, 81693057596, 257287858063, 810314166891, 2552040558803, 8037513448351, 25313713063685, 79724167578475

Offset

0,1

Links

Colin Barker, Table of n, a(n) for n = 0..1000

Maple

A022020 := proc(n)
    option remember;
    if n <= 1 then
        op(n+1, [3, 9]) ;
    else
        a := procname(n-1)^2/procname(n-2) ;
        if type(a, 'integer') then
            a+1 ;
        else
            ceil(a) ;
        fi;
    end if;
end proc: # R. J. Mathar, Feb 10 2016

Prog

(PARI) a=[3, 9]; for(n=2, 30, a=concat(a, a[n]^2\a[n-1]+1)); a \\ M. F. Hasler, Feb 10 2016

Crossrefs

Sequence in context: A118365 A095716 A124820 * A195675 A170953 A358092

Adjacent sequences: A022017 A022018 A022019 * A022021 A022022 A022023

Keyword

nonn

Author

R. K. Guy

Extensions

Double-checked and extended to 3 lines of data by M. F. Hasler, Feb 10 2016

Status

approved